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A Variational Monte Carlo Study of the Current Carried by a Quasiparticle

Cody P Nave·Dmitri A. Ivanov·Patrick A. Lee
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Abstract

With the use of Gutzwiller-projected variational states, we study the renormalization of the current carried by the quasiparticles in high-temperature superconductors and of the quasiparticle spectral weight. The renormalization coefficients are computed by the variational Monte Carlo technique, under the assumption that quasiparticle excitations may be described by Gutzwiller-projected BCS quasiparticles. We find that the current renormalization coefficient decreases with decreasing doping and tends to zero at zero doping. The quasiparticle spectral weight Z_+ for adding an electron shows an interesting structure in k space, which corresponds to a depression of the occupation number k just outside the Fermi surface. The perturbative corrections to those quantities in the Hubbard model are also discussed.

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Cody P Nave, Dmitri A. Ivanov, Patrick A. Lee. 2005-09-30. A Variational Monte Carlo Study of the Current Carried by a Quasiparticle. https://doi.org/10.1103/physrevb.73.104502

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